主动型自动喷水灭火系统研究

针对传统自动喷水灭火系统存在响应时间长、水渍损失大的缺点,提出了主动型自动喷水灭火系统的研究方案。通过新型探测组件、电加热洒水喷头以及算法编程等技术,实现自动喷水灭火系统的主动性和智能性。搭建试验平台,针对角落火灾、边界火灾、中间火灾,分析系统火灾探测性能和洒水喷头启动情况。试验结果表明,主动型自动喷水灭火系统能够实现早期探测火源位置,主动电加热启动相应位置的组群洒水喷头,扑灭初期火灾,同时减小水渍损失。     

现代汉英消防词汇

[续上期 ]xi ng【响应时间】(消 )　Response Time由火灾自动报警系统发出火警信号起 ,至系统中最不利点水雾喷头喷出水雾的时间。【响应时间指数】(消 )　Response Time Index闭式喷头热敏性能指标 ,简称 ( RTI)。响应时间指数即量化喷头热敏性能的参数 ,是由美国工厂联合研究所于 1981年提出的。响应时间指数是用喷头热敏元件的时间常数 ( τ)与相关热气流速度 ( u)的平方根乘积表示 :RTI=τ· μ0 .5,公安部天津消防科学研究所用 10只喷头试样测得的 RTI平均值如下 :自动洒水喷头响应时间指数实验数据喷头类别开放时间 s RTI( m0 …     

直立型分体洒水喷头的设计与试验

为缩短自动喷水灭火系统喷头探测响应时间、提高灭火效果,提出了将响应元件和喷洒口分开的设计思路,设计了一种直立型分体洒水喷头,以代替集热板在实际工程中的应用。在此基础上测试该喷头的应用效果,通过改变火源位置,对比直立型分体洒水喷头、加设集热板的喷头和普通闭式喷头的响应时间和附近温度变化情况,分析了直立型分体洒水喷头的特点与优势,确定了其适用场所。     

CMSA喷头动态热性能研究

采用风洞试验方法研究下垂型和直立型CMSA喷头的动态热性能,分析总结CMSA喷头的导热系数和响应时间指数的特点。导热系数由等速率升温试验计算。可以考虑采用ESFR喷头的计算公式计算CMSA喷头的导热系数和响应时间指数,采用普通洒水喷头的分类将其归入标准响应喷头的范围。     

自动喷头的发展

自动喷头是自动喷水灭火系统的关键部件,系统的灭火效能受到喷头开放时间、火灾燃烧特性、洒水密度的影响,喷头开放时间在上述影响因素中占主导与支配地位,而喷头的热敏性能将决定火灾发生后的喷头开放时间,从而决定灭火的时间和效果,因此,掌握喷头热敏性能,寻找合适的热敏元件,喷头形状是保证自动喷水灭火系统效能的基本方法,也是喷头研究     

辐射热启动喷头的研究

为解决传统闭式洒水喷头安装的局限性,分析了传统闭式洒水喷头的吸热方式,揭示了传统闭式洒水喷头不能有效吸收辐射热的原因。根据辐射热的基本原理,提出了提高喷头感温元件吸收辐射热的方法并设计研发了辐射热启动喷头。为验证辐射热启动喷头的启动优势,进行了辐射热源和油盘火试验,对辐射热启动喷头和传统闭式洒水喷头的启动性能进行了对比研究。结果表明,在无法与热烟气进行对流换热的情况下,辐射热启动喷头能够通过吸收辐射热而启动。分析总结了影响喷头启动速度的因素以及在实际火灾条件下,辐射热启动喷头的热交换情况。     

超大口径低水压快速反应早期灭火型洒水喷头

中央公司的 UL TRA K2 5型 ESFR超大口径快速反应早期灭火型洒水喷头 ,可以在无需高压及货架内设洒水喷头的条件下 ,接受高危险性的火灾挑战。快反应速度、水滴大小以及水流速率等其它优良性能的组合 ,使其能对较严重的火灾进行早期灭火。经认可 ,超大口径快速反应早期灭火型洒水喷头能在室内高度为 4 5英尺 (13.7米 ) ,货物堆高至 4 0英尺 (12 .2米 ) ,并且可在溅水板离天花板的最远距离达18英寸 (45 7毫米 )的情况下使用。此距离大于 K14型ESFR洒水喷头 ,有利于工程安装和使用。与 K14型一样 ,只有下垂式洒水喷头。超大口径快速反…     

5mm玻璃球洒水喷头的研究

5mm玻璃球洒水喷头(以下简称5喷头)是一种应用新技术的喷头,也是自动喷水灭火系统中的关键部件,它由热敏元件——(?)5玻璃球、密封组件、溅水盘和喷头本体等组成。其反应时间比8mm玻璃球洒水喷头要快,直接影响火灾的扑灭和控制程度。     

齐平式洒水喷头动态热性能研究

采用风洞试验方法研究齐平式洒水喷头的动态热性能。喷头公称动作温度为72、96、139℃,风温为197、300、407℃,气流流速为(1±0.1)m/s,气温以(1±0.25)℃/min的速率上升,直至喷头动作。考察温度等参数对导热系数、响应时间的影响。结果表明:齐平式洒水喷头的导热系数(C值)和响应时间系数(RTI值)符合国家标准GB 5135.1-2003。风洞试验结果简单、可重复且数据可靠。     

无侧限屋顶下自动喷水灭火系统启动临界状态的计算和实验

利用火灾模化理论、喷头响应时间指数 RTI概念及 Alpert对火灾水平热气流状态量化理论 ,建立了预测无侧限屋顶下闭式喷头启动临界状态的计算方法 ,并对计算结果进行了实验验证。     

Assessing the Sprinkler Activation Predictive Capability of the BRANZFIRE Fire Model

This paper describes an investigation into the sprinkler response time predictive capability of the BRANZFIRE fire model. A set of 22 fire/sprinkler experiments are simulated where the sprinkler activation time and the heat release rate (HRR) for each individual experiment had been determined. The experiments provided data for use in validating the sprinkler activation prediction algorithms in the BRANZFIRE zone model. A set of base case values were chosen and input files constructed for the simulations. The experiments were then simulated by the fire model using both the NIST/JET ceiling jet and Alpert’s ceiling jet options (which are the two ceiling jet correlations available in the BRANZFIRE zone model). The fire model included a heat transfer calculation for the temperature of the heat sensitive sprinkler element. Different sprinkler operational parameters such as the conduction factor, response time index (RTI) and the sprinkler depth below ceiling were also varied to assess the sensitivity of their effect on the activation time. Results showed that using the NIST/JET ceiling jet algorithm gave a closer prediction of the sprinkler response time in a small room than Alpert’s correlation. This was expected, since the former includes the effect of a hot upper layer while the latter applies to unconfined ceilings. The experiments available for comparison had been conducted inside an enclosure with a developing hot upper layer. The findings also signified that changing the sprinkler operational parameters can change the predicted sprinkler activation time significantly.     

自动喷水灭火系统喷头基本特征参数对比与选用分析

改善消防喷淋喷头性能及新品种的开发是为自动喷水灭火系统中的研究热点。结合喷头的流量系数、热敏指数（RTI）等各征参数及一些工程实际中的使用情况,对闭式喷头的适用场所及选用时应注意的几个方面进行了比较与说明,为设计应用项特自动喷水灭火系统时喷头的选用提供方便。     

设置自动喷水灭火系统保护防火卷帘的探讨

作者根据国家现行规范的要求，对防火卷帘设置自动喷水灭火系统的喷头类型、间距、喷头与卷帘的距离及管网连接方式、管网工作压力、用水量计算等问题进行了讨论。     

Experimental Investigation of an Office Fire with a Partially Impaired Sprinkler System

In this work, an actual office fire with a partially impaired automatic sprinkler system was investigated. As per regulations, there were four sprinklers in this model office. In the research conducted here, the first three sprinklers were actuated without water supply, while the last sprinkler was supplied with water at the required operating pressure for a period of 30 min. The fire source, a burning plastic trash can filled with 0.5 kg of paper, burned the adjacent chair, desk, desktop computer, and then reached the interior wooden furniture. The results show that the single remaining sprinkler effectively controlled the fire spread for 30 min. The partially impaired sprinkler system does not completely extinguish the fire, but extends the available time for evacuation. Continuing the discharge from sprinklers is preferable since the heat release from the fire increased after water flow was terminated.     

SMART Sprinkler Protection for Highly Challenging Fires—Part 1: System Design and Function Evaluation

An experimental study was conducted to prove the concept of a new protection system—a sprinkler system that uses Simultaneous Monitoring, Assessment and Response Technology (SMART). The present work focuses on the system design and function evaluation at the component level. The objective is to demonstrate the feasibility that the SMART sprinkler system can provide adequate protection to highly challenging fires. The new protection system has several key functions including multi-sensor detection, real-time fire location calculation, dynamic sprinkler activation and wireless communication coordinating the system components. A series of fire detection, sprinkler activation and fire suppression tests were carried out to evaluate these system functions. Results show that a combination of smoke and temperature sensors can detect the fire at a very early stage, with the fire size reduced by one order of magnitude, and provide sufficient data to locate the fire. A thermal centroid based algorithm can determine the fire location within less than 50% of the sprinkler spacing on average. The sprinkler activation (six units) concentrating water discharge in the vicinity of the fire can suppress and even extinguish the fire under certain experimental conditions. These results confirm that the design objectives have been achieved. The experimental data also provide crucial information to assess system performance in full-scale tests.     

自动喷水灭火系统在隧道中的应用与发展趋势

随着隧道火灾的频繁发生,关于隧道中能否采用自动喷水灭火系统的问题成为该领域的研究热点.介绍了自动喷水灭火系统在国内外隧道中的应用现状,总结了隧道中采用自动喷水灭火系统的优缺点及存在的争议.根据国外对隧道中自动喷水灭火系统进行的试验评估,指出该系统可以降低隧道温度并能防止火势蔓延,具有良好的应用前景.     

The Response Time of Different Sprinkler Glass Bulbs in a Residential Room Fire Scenario

The response time of fire sprinklers is essential for their performance, especially in applications where life safety protection is desired. The earlier the sprinkler activates, the smaller the size of the fire. Most commercial residential sprinklers are fitted with 3 mm, 68°C glass bulbs. However, thinner sprinkler glass bulbs with lower operating temperatures are available. The aim of this study was to determine the response time—and the corresponding heat release rate—of different glass bulbs in a residential room fire scenario. A series of tests were conducted inside a compartment measuring 3.66 m by 3.66 m having a ceiling height of 2.5 m. The compartment was either enclosed or had two walls removed to provide a more ventilated scenario. A propane gas burner was positioned at one of the corners. The mass flow rate of the gas was controlled such that either ‘slow’, ‘medium’ or ‘fast’ fire growth rate scenarios were simulated. In each test, nine Response Time Index (RTI) and operating temperature combinations were tested. Each test was replicated three times. In addition, two commercial fire detectors were tested. The results show that the fire is considerably smaller upon activation with a combination of a low RTI and a low operating temperature, as compared to the 3 mm, 68°C glass bulb typically used for residential sprinklers. The operating temperature proved to have a larger impact on the results than the RTI. The heat from the fire was typically detected by the fire detectors prior to the activation of the sprinkler glass bulbs, especially for the ‘slow’ and ‘medium’ fire growth rate scenarios.     

自动喷水灭火系统的抗震设计

自动喷水灭火系统的抗震措施应在设计和安装时予以考虑,以确保在地震发生次生火灾时能正常发挥作用,保护财产安全.自动喷水灭火系统抗震设计的方式主要有抗震支撑、柔性连接及设置间隙三种方式.